Clamp



April 13 192s. 7 1,580,197

J. M. HARGRAVE CLAMP Filed Sept. 29. 1924 UNITED STATES,

PATENT OFFICE.

JOHN M; HARGRAVE, OF CI-NCINNATI, OHIO.

CLAMP.

Application filed September 29, 1924. SeriaLNo. 740,421.

To all wZt JWL may concern:

Be it known that-"I, J oHN M. HARGRAVE, a citizen of the United States, and residing at Cincinnati, in the countyof Hamilton and State otOhi0,hav'einvented anew and use-: iul Glamp, of which'the following spec .ticationis a full disclosure.

This invention relates generally to improvements in clampingdevices primarily of the class known as saw clamps, in which the clamping jaws can be separated to a very limited degreewith a quick acting control for the movable jaw. An object oi the invention is to provide a device of the above nature which maybe conveniently attached to a support, the

n'iountin'g for the pressure-applying portion of the attaching means being pivotally secured and adapted to be folded within and against the base or support-enga'gingi portion of the apparatus. p

Another objectis to provide a floating re silien'tly suspended movable clamping memher or jawnormally held in: spaced relation to its companion stationary member and movable theretoward' against spring action providing for ready insertion of the work,

and for retraction of the movable member fromengagement with the work upon its release by the clamping means.

Another object of theinvention is'to provide a clamphaving cooperative stationary andniovahle jaw members in which the movable jaw member is swin 'ingly suspended upon bowed supports which are themselves relatively yieldable or springy tocompensate fordifierence in thickness of the articles to be chimped, said support, however, having sufficient rigidity to procure the properclamping action between the jaws under all conditions.

Other objects are to provide a device which can be manufactured at small cost, which will withstand relatively great cl amp-- Y ing strains, which is of relatively small di mensions,;and which has a minimum weight.

Another object of the invent-ion is the provision of :1 cam and cam actuating means formed from a single length of wire and op erable for simultaneously engaging-"the.- movthe d-rawings' forming part of this specili cation, in which :I

Figure 1 is a front elevation of the device. 4

Figure 2 is a plan-view.

Figure 3 is a vertical transverse section on line 33 of Figure 1 showing the clamp in released position... a

Figure. is a. fragmentary detail showing thedevice in clamping!position. i

he clamp isprincipally made troinangle and channel iron bar stock adapting a simple and durable structure at a minimumcost of manufacture.

The device comprises a statio-nar 1 j aw member and a movable jaw member coop-- erable therewith. The stationary jaw 'or. clamping member 1 is adapted to be attached to" a support and is formed from a. length of angleiron, in this instance, having unequal flanges'or lin1bs,.the shortest of which provides the stationary'jaw portion against which the work is clamped. The ion er flange formsa plate orjbase portion for hearing upon a support or" table to which the clamp is secured. Centrally of the short flange at the inner side; is pivoted a length o channel 11-0112 having its channelside. facing away from the flange. The iron; is curved at'ils free end to pr :ide a: rightangularly disposed extension in threaded en gagement with which is a clamping screw 3 having a" winged finger piece or squared portionby which it can be forcibly rotated. The screw is adapted to engage at the under side of the support in the usual manner Figurei). lVhennot in use this device may be swung 'to'lie flatly against the rear side of the short flange'of the iron, which is the preferable position, when being transported.

The long flange of the member 1: at an opposite end is notched as at 4, by removing a of these projecting portions at the rear is fastened one leg 6 of a substantially U- shaped or bowed support. Each support projects upwardly at an angle to the long axis of the member 1, preferably at the right angle, and has its free or unattached leg 7 spaced outwardly from and disposed in opposition to the work face of the angle iron 1, preferably substantially parallel there with. The spacing is suii'icient to permit the introduction and movement of a movable clamping member, between the leg and the working face of the stationary member. Each bowed support is formed from. a length of channel iron, the concave or channel side facing outwardly, and thus providing a rib reinforced relatively yieldable support to which the movable member is attached.

Although the preferable shape of the )OWBLl supports is that herein shown, any desired shape may be given them, if a free, relatively yieldable leg is provided, spaced from and disposed in opposition to the work face of the stationary member, and which is sufiiciently rigid to procure proper clamping action, but will give enough to allow work of greater thickness to be clamped. Attached by one end to and preferably at the apex, inside of and flatly against the plane face of each support is a resilient element 10 having herein the form of a leaf spring.

The upper end of the spring is curved to conform to the curved outline of the sup port at the pointof attachment and is secured thereto by a screw 11. The element is bent inwardly away from the free leg and disposed at an intermediate point and extends downwardly substantially to a point in opposition to the lower edge of the work engaging flange.

The movable clamping member is herein formed from a length of channel iron with its concave or channel side opposing the work face of the stationary member, thus providing two spaced elongated, longitudinally disposed relatively narrow faced ribs 16, the faces of which engage the work and thus have virtually a biting edge contact therewith. The length of the member is substantially the same as that of its companion member and its ends lie between the free legs and the support, and each is attached by a screw 17 to the lower end of a resilient element 10, the elements thus swingingly supporting the member. The member 15 is preferably slightly curved longitudinally with the convex side facing the member 1 so that when engaging the work and pressure is applied at the ends the member is flattened and positively engages the work at every point.

The springs or resilient members are shaped and disposed in such manner that when the member is attached it is yieldably suspended and spaced from the member 1 suliiciently to permit the freeinsertion of the work. he springs also act to retract the movable member to release he work after the advancing means has been released, the detail of this means being described herebelow.

This construction simplifies the assembly of the device, the springs ordinarily being first attached to the movable bar, inserted jection 21 formed by bowing the wire. Ato each side of the grip portion the wire is twice rightangularly bent and after the second bend providing coaxial bearing engaging portions 22, each of which is rotative in two bearings or lugs 23, 2 attached to and extending outwardly from the movable member, a bearing Qlbeing adjacent each free leg of the supports. The terminals of the wire are bent at right angles to provide relatively short cam portions and the tips of these bent portions are rounded concentrically with the rotative axis of the device for engagement with the inner wall of the leg 7 against which they impinge when the shaft is appropriately rotated, and forcibly swing the clamping member toward and into contact with the work. The grip portion and projection 21, and the cam p0rtions are angularly related in such manner that when in clamping position the projection 21 engages the work, the iron 2, or the support to which the apparatus is attached, stopping the cams in a position to prevent accidental release while the work is being operated upon (see Figure This is accomplished by having the cams pass slightly over or beyond a line intersecting the rotative axis of the device, and substantially perpendicular to the outer face of the mov able member, which position I designate over-the-center-lock for cam operating lever.

Although the locking device herein shown and described is preferable, other equivalent means could be used, providing that pressure be applied at a point between the free leg and he movable member, for example, the locking device could extend between the free legs and be pivoted thereon, or separate clamping devices independently operable could be placed upon each leg. the over-the-center-loclr is preferable but any equivalent means can be provided for forcing the yieldably mounted movable member to clamping position.

lVith the movable member thus yieldably Moreover,

suspended in spaced relation to the station:

ary member the work can beeasily intro.-- duced and when the work; is of greater thickness than the d stance of; the spacing,

the yieldability permits the member tobe easily forced awa'yto permit its introduc,-'

tion. As ordinarily used, however, theworlr is generally of less" thickness than the "spaer ing and the work can be freely introduced and when the clamp bar 15 is released. the work is also released. I a

Haring described the invention, I claim:

1. In a device of the class described, a first clamping member having a work; face, bowed supporting members attached, in spaced relation, to said clamping member,

each having a leg spaced from the work.

face of the member, a resilient element. for each bowed supporting member secured at one end to the bowed supportmg member,

having its freeend intermediate the leg andwork face, a second clamp. member connected at opposite .ends to said respective resilient elements and havin' 3. work face cooperable with thatof the fir member,vv by swinging against the ,spring action, and means coopera-ble with the legs and movable nember for forcibly advanc-.

ing the member to clamping position and holding the same thereat. v

' 2. In a device of the class. described, a first clamping member, bowed. members attached at opposite ends thereof, eaoh'having an unattached leg spacedtherefrom, a spring attached one at the inner-side of "each of said. bowed members, asecon'd clamping member cooperable' with the first having portions thereof lying between the unattached leg and thefirst member and at'-. tached to and suspended by said.spr1ng,and-

means cooperable with the legs and second member, for forcing said member toward the first.

8. In a device of the class described, a' first clamping member, bowed members at-- tached at opposite ends thereof, each having an unattached legrspaced therefrom, a spring attached one at the inner side of each of said bowed members, a second. clamping .member' cooperable with the first having portions thereof lying between the unat'' tached leg and the first member and attached to and suspended by said spring, and means" cooperable with the legs and second member for forcing said member. toward the first, and holding the same in advanced position.

4f. In a device of the class described,'an angle iron adaptedv to be fitted over'the corner of a support and. having a work engaging face, a yieldablebowed. support attached-at each end of theiron, eachsupport having afree'leg s'paced'from the work;

face of the iron, a resilient element attachedftogand depending from each support at the inner side thereof, a channel st mentioned iron hav-ing the end faces of its flanges cooperable with the work face, of the angle iron,'and attached to the resilient elements, means eooperable with the channel iron and free] legs for forcibly advancing that iron toward the other, for clamping work between the two, and means for lock- 'ing thead-vancing means when advanced.

' neo 'islycooperable with the unattached legs for forcibly moving the clamping member toward and against the stationary member,

'and' automatically locking said camm'eans as then disposed 6,111 adevice of the class described, a stationary member having a plane face for engagement by the .work, substantially U- shapedsupports, each attached by one leg adjacent opposite ends of said member, with the free legspaced from andinopposition to the work face, a resilient element attached to each support atone end, between the legs,l

a. movable clamping member withjeach end, attached to the corresponding resilient ele ment, and means mounted upon the movable.

clamping member cooperablegwiththe un-- attached legs simultaneously operable for forcibly .moving .the .movable. member against the'stationaiiy member.

'7. In a device of the class desc ibed, a stationary member having means thereon to: clamp the same to a support, andhaving a plane face. for engagement by work, Ursha'ped.supporting elements each attached by one. leg atrelatively opposite lends-of the member 'in' inverted position, each having a legsp'aced from: and opposingly related "tothe member, leaf springattached depend- .ingly between the legs of each supporting element, a-movableclamping memberadapted for cooperation with the stationary member for clamping work, between the members, the respective ends of the clamping member attached to said leaf springs, the

springs supporting the member formovement. againstspringaction toward the stationa-ry, member, andmeans for forcing 'the movable member against the stationary member.Z f

8. In..a,device of the class described, a

stationary member; having means thereon to clamp; the same to a support ElIlClflllttYlDgl a planefaceagtalnstwhich work 1s adapted.

action toward the stationary member, and

means rotatably pivoted upon the movable member for forcing the same against the stationary member, said means comprising a single length of heavy wire bent to provide an intermediate grip or handle portion, oppositely extending coaxial bearing engaging portions, and torn'iinal angular cam portions tr-ngageable with a free leg, the grip portion and cam portions angularly related for obtaining oventhe-center locking position of the c. i s when the grip portion engages the work or stationary support.

9. In a device of the class described, a stationary member having means thereon to clamp the same to a support and having a plane facfor engagement by the work, bowed supporting elements each attached by one leg at relatively opposite ends of the member in inverted position, each having a leg spaced from and opposingly related to the member, a leaf spring attached by one extremity dependingly between the legs of each supporting element, a movable clamping member adapted for cooperation with the stationary member for clamping work between the members, the ends thereof extending between the stationary member and free legs, each end attached respectively to the correspoiu'ling leaf spring, the spring supporting the movable member spaced from the stationary member and for move ment against spring action toward the stationary member, and means for forcing the movable member against the stationary member, said means comprising a shaft rotatably mounted upon the movable member having cams at opposite extremities cooperable with the free leg of the supporting element for forcing the member to clamping position when the shaft is rotated.

10. In a device of the class described, a first clamping member having a plane work engaging face, U-shaped elements each attached in inverted position by one leg to pposite ends of said stationary member, each having a free leg spaced from and opposingly related to said work face, a leaf spring attached at one end within and to each U- shaped element, and extending downwardly between the legs andv work face of the stationary member, a movable clamping memengaging face, and means for clamping the member to a support, bowed supports one attached by an extremity adjacent each end of the member, with the unattached portion spaced from and in opposition to the work face of the member, resilient elements onefor each support terminally attached within the supports, movable clamping member having respective opposite ends attached to the corresponding free ends of the respective resilient element, and cam means simultaneously cooperable with the unattached portions of the supports for forcibly moving that member toward and against the stationary member or work.

12. In a device of the class described, a stationary clamping member having a Work engaging face, and means for clamping the member toa support, bowed supports one attached by an extremity adjacent each end of the member, with the unattached portion spaced from and in opposition to the work face of the member, resilient elements one for each support terminally attached within the supports, a movable clamping member having respective opposite ends at tached to the corresponding free ends of the resilient element, and cam means upon the movable member simultaneously cooper-able with the unattached portions of the supports for forcibly moving that member toward ant against the stationary member or work, and automatically locking the same in advanced position.

13. In a clamp of the class disclosed, a stationary jaw member having support extensions reaching forward of the jaw surface of said member, for supporting a movable jaw member, a movable jaw member yieldingly dependingly secured to said support extension between the support extension and stationary aw member to be automatically retractable from said stationary.

1,5so,197 V 5 ieldable support extensions reaching for jaw member cooperating with said support wardly oi the jaW- surface of said member extensions for forelbly moving said movable I for supporting a movable jawmember, a aw member toward said stationary jaw 10 movable jaw member dependingly secured member. y Y to said support extenslon, retractable from In Witness whereof, I hereunto subscrlbe said stationary jaw member, and a clampmy name. I ing member mounted upon said mouable I JOHN M. HARGRAVE. V 

